EDHREC, CEDH Decklit Database and countless YouTube Videos come to mind
Whether youre tutoring up your Sol Ring or something else altogether like The Ozolith or Shadowspear this is an invaluable effect to have around
Similarly, had I on turn 1 attached a water energy to my benched Staryu instead of my active Goldeen, I would have been prevented from progressing when I ended the turn instead of when I attached the energy card
Ledger Shredder If theres a card that has impacted multiple formats, including eternal ones like Modern, it has to be Ledger Shredder
It's even better in a deck like Nevinyrral, Urborg Tyrant
Mentor (Whenever this creature attacks, put a +1/+1 counter on target attacking creature with lesser power.) Whenever a nontoken creature you control dies, if it had counters on it, create X tapped 2/1 white and black Inkling creature tokens with flying, where X is the number of counters it had on it